1. Field of the Invention
The present invention relates to a video image appreciation system with a self-luminous display and a circularly polarizing light source mounted outside the self-luminous display.
2. Description of Related Art
Conventionally, self-luminous displays in which polarizing films, quarter wavelength plates, and self-luminous panels are disposed in order are known as self-luminous displays with antireflection functions (For example, Japanese Unexamined Patent Publication No. 1997-127885 A).
FIG. 4 shows one example of a conventional self-luminous display 40.
(1) Natural light 42 emitted from a natural light source 41 passes through a polarizing film 43 and is converted into linearly-polarized light 44. The direction of the vibrating surface of the linearly-polarized light 44 is a transmission axis direction 43a of the polarizing film 43.
(2) The linearly-polarized light 44 passes through a quarter wavelength plate 45 to be converted into circularly-polarized light 46.
(3) The circularly-polarized light 46 reflects on a surface of a self-luminous panel 47 to convert its rotation direction into reverse circularly-polarized light 48 (For instance, if the circularly-polarized light 46 is clockwise circularly-polarized light before reflecting, the circularly-polarized light becomes counter-clockwise circularly-polarized light after reflecting).
(4) The circularly-polarized light 48 after the reflection passes through the quarter wavelength plate 45 to be converted into linearly-polarized light 49. The direction of the linearly-polarized light 49 is an absorption axis direction 43b of the polarizing film 43.
(5) Since the linearly-polarized light 49 is absorbed into the polarizing film 43, outside light having reflected on the surface of the self-luminous panel 47 does not reach an observer 50.
(6) On the other hand, displayed light 51 (video image) emitted from the self-luminous panel 47 is natural light, so that the displayed light 51 is turned into natural light 52 being unchanged to be incident on the polarizing film 43 without any influence of the quarter wavelength plate 45 and then is turned into linearly-polarized light 53 to reach the observer 50.
In this way, it is possible to increase a contrast in video images by inhibiting outside light reflection on the surface of the self-luminous panel 47.
However, in the conventional self-luminous display 40, when the displayed light 51 (video image) emitted from the self-luminous panel 47 passes through the polarizing film 43, about one half of the amount of light is absorbed into the polarizing film 43. This raises a problem of the dark display screen.
Further, it was necessary to make the room dark (reduce outside light) when appreciating high-definition video images because the conventional self-luminous display 40 does not have sufficient antireflection functions. Accordingly, video image appreciation systems with self-luminous displays capable of displaying high-definition and high contrast video images without the necessity of making the room dark have been demanded.
It is therefore an object of the present invention to provide a video image appreciation system with a self-luminous display which is capable of displaying high-definition and high contrast video images without making the room dark.